Today was a build day. I made the frame for the roof of the tower, and practiced with my new foam cutter by making a circular platform.
Here's the tower, with the roof framework:
The whole thing will be covered with rows of shingles. It's got a lower angle than the last one, but the sheathing doesn't go down as far. I'm hoping that won't hurt the stability of the bottom row of shingles too much.
And then, the platform:
It's just a disc of insulation foam that's been given wood texture with a wire brush, and then had 'boards' traced in with a pen. Pretty simple, and it didn't take long to make at all.